But they were wrong, said Warren McCullough, chief of the state Department of Environmental Quality's Environmental Management Bureau.
What happened next depends on your point of view and is the central issue in the debate over Initiative 147, an effort to repeal the state's ban on cyanide leach mining. Either we spent years learning the realities of the cleanup and its costs and are now better able to properly run such mines today. Or we have learned that these mines are simply too dangerous, too expensive and too often left to government to clean up to allow any more to open.
In a nutshell: Gold ore is mined in open pits and cyanide is used to leach the gold from the ore in lined piles called heaps. The technology allows mines to go after low-grade gold ore.
According to conversations with miners, engineers and state regulators, cyanide has been used to extract gold from ore for more than 100 years. Gold dissolves in cyanide, like Alka-Seltzer in water, and the process to extract it with cyanide is relatively simple: Once mined, the ore is typically ground in massive machines to better expose the gold particles. Then, a cyanide solution is trickled over it. The solution is then captured and processed to extract precious metals.
Cyanide, although poisonous, will readily evaporate in rivers and lakes, according to the U.S. Centers for Disease Control and Prevention's Agency for Toxic Substances and Disease Registry. It is present in small amounts in a host of unlikely places, like lima beans and almonds. But it is a potent killer - Adolf Hitler and his wife, Eva Braun, both killed themselves by crushing cyanide capsules in their mouths. (Hitler hastened his death by also shooting himself in the head.)
In mining, cyanide spills can cause fish kills and other problems, most recently at a river downstream from a gold mine in Ghana last week.
While cyanide in mining is nothing new, using heap leaching to process gold didn't come along until the 1970s, McCullough said, when the first such mine was opened in Nevada. The process opened up the door to mining ore previously considered marginal at best because it allows miners to extract tiny pieces of gold widely diffused through much larger lower-grade ore bodies.
Among the first major cyanide leach mines in the country was Montana's own Zortman and Landusky mines near Malta which opened in 1979. Owned by the now-bankrupt Pegasus Gold, the Zortman and Landusky mines grew from 529 acres in the late 1970s to 1,215 acres by the time they closed in the late 1990s, information from the federal Bureau of Land Management shows.
Mining in that corner of the Little Rocky Mountains was nothing new, according to the BLM. Prospectors first started digging around the area in the 1880s, and in 1895 a mineral-rich chunk of mountains was bought from the Assiniboine and Gros Ventre tribes of the Fort Belknap Reservation - which surrounds the mining district on three sides.
In 1992, regulators found at the site one of the most thorny problems caused by open pit mines: acid rock drainage, BLM information shows. Acid rock drainage occurs when certain rocks form sulfuric acid when exposed to oxygen and water. The acid leaches other minerals from surrounding rock.
Pegasus Gold filed for bankruptcy in 1998.
Most of the company's mines were closed and left to either the state or federal government to clean up. A few properties, including the Montana Tunnels gold mine in Jefferson City and the Diamond Hill mine near Townsend went to a new company called Apollo Gold.
Even back in the 1970s, companies had to post a reclamation bond before they could start mining, said Wayne Jepson, a DEQ hydrologist. A reclamation bond is something like a multimillion dollar damage deposit to be used to clean up defunct mines should the company fold or be unable to clean up the mine itself.
But in the case of Zortman and Landusky - and a lot of other defunct gold mines - the reclamation bonds weren't large enough to clean up everything, McCullough said.
The state - which hired an engineering firm to do the work - has spent most of the $30 million reclamation bond to make the site look more natural, a process which is mostly complete, said Jepson. The once stark, terraced pits and giant mounds of mine waste at Zortman and Landusky have been largely recontoured and planted with a mix of native and other grasses. The mountains may never look as they did before the mines opened, he said, but green grasses are now coming in all over the newly rounded hillsides.
The problem is the water.
Water running off the site is contaminated and will have to be treated forever, Jepson said. Right now, two water treatment facilities clean water running down the creeks draining off of both mines. The technology is relatively simple and inexpensive, but there isn't money left in the old Pegasus reclamation bond to pay for perpetual water treatment.
The state has enough money to treat the water for another 13 years, Jepson said. But he estimated the state needs an extra $20 million invested today to pay for the perpetual water treatment necessary. Every year that the money is not invested only drives up the future cost.
Not every open pit cyanide leach mine in the state is so problematic. The Golden Sunlight Mine, owned by mining powerhouse Placer Dome, initially had a series of environmental hang-ups, but has found and fixed them, McCullough said. Golden Sunlight uses a much older technology called vat leaching, where the crushed ore is treated in vats of cyanide solution. However, McCullough said, the mine is often paired with heap leach mines because it processes low-grade ore.
Back in 1983, cyanide solution leaked through the layer of clay lining under one waste pond, said Shannon Dunlap of Golden Sunlight. The pond was built with an older technology no longer used at Golden Sunlight.
The solution managed to escape an underground dam built to catch just such a leak and turned up in one of the mine's many groundwater monitoring wells. The mine fixed the underground dam and started pumping the contaminated groundwater back into the mine's water containment system.
"In our wells down gradient from the site, cyanide meets drinking water standards," Dunlap said.
Also, the mine used to discharge a cyanide-laced slurry into a pond, where the water would be recaptured and reused. But, migratory birds had a bad habit of trying to land on the pond, prompting the company to launch an aggressive, round-the-clock bird-hazing effort. Then, about six years ago, the mine started treating the water to destroy any cyanide - an expensive process, Dunlap said, but one that could put to rest the need for full-time bird hazers.
Golden Sunlight has also spent about $17 million reclaiming the mine's massive waste rock piles, he said.
"We're pretty happy with the work that's been done," he said. "We've had pretty good success."
The rock piles have been reshaped, covered in topsoil and planted with grasses designed to blend in to nearby hillsides. Deer, game birds and other animals are a common sight, Dunlap said. The reclaimed rock piles are indistinguishable from surrounding terrain in places.
Golden Sunlight has also conducted some research on how to prevent or treat the acid rock drainage found inside the Golden Sunlight pit.
In addition, the mine has posted a $54 million reclamation bond - $24 million more than Zortman and Landusky, which were much larger mines.
Some of the problems associated with open pit cyanide leach mines stem from the general ignorance everyone had about them when most of the mines were opened, McCullough said, and from the relatively modest reclamation bonds the state required.
"We had very simple notions about the complexity of ending heap leach mines," said Patrick Plantenberg, supervisor of DEQ's operating permits section.
But instead, he said, the mines have proved far more environmentally complicated, especially when it comes to water quality.
It was in the wake of the Pegasus bankruptcy that Montanans passed Initiative 137, the initiative that banned open pit cyanide leach mining. Jim Jensen, executive director of the Montana Environmental Information Center and head of the group that pushed for I-137, said he concluded, after visiting a series of such mines, that the technology just couldn't work safely.
I-137 banned that one particular kind of mining, he said. Underground gold mines could still use cyanide to leach gold from ore and open pit mines can use some other method. But open pits and cyanide leach used together became illegal on Election Day 1998.
Jensen said the technology is inherently dangerous for two reasons: cyanide and the enormous open pits cyanide leaching makes possible.
"It's simply a failed technology," Jensen said.
Most of the large open pit cyanide leach mines ever opened in Montana are now closed and in the hands of either the state or federal government to clean up. Consequently, McCullough said, the state knows a lot more about cleaning up and closing an open pit leach mine, although he said there may still be some surprises.
That hard-won knowledge is exactly why Montanans should vote for I-147, said Tammy Johnson, spokeswoman for Miners, Merchants and Montanans for Jobs and Economic Opportunity, the committee pushing for I-147. We are not doomed to repeat the mining mistakes of the past," she said. With a more accurate understanding about how expensive and complicated cyanide leach mines are to close, Montana has the chance to do it right.
"It's been a long time since Zortman and Landusky were permitted," she said. "None of them were permitted to the standard we have now."
|
 |
 |
Add your comment now! Write your comment in the form below.
(Email address is for verification only. If you'd like to email a story, look for the link above)